The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
This invention relates to the hydrocarbon production industry and can be implemented for increasing the productivity of wells by preventing fractures from closure through the use of propping granulated material (proppant) during a fracturing operation of a petroleum bearing subterranean formation.
Formation hydrofracturing is considered as one of the most promising technologies in petroleum industry, which allows increasing a well production, provided that this technology is applied properly. The essence of the proposed method lies in injection under a high pressure of a viscous fluid into hydrocarbons-bearing formations to produce fractures in the said formation; the fractures provide the paths for transport of formation fluids. To keep the fractures partially open, mechanically strong spherical grains (proppant) are delivered into the fracture; the proppant is inert to the well fluid. The proppant fills (at least partially) the fracture to develop a strong wedged-out composition, which is permeable for formation fluid. Proppants, being artificially manufactures grains, should not only withstand a high formation pressure that tends to deform proppant particles (thus leading to an inevitable closing of the fracture), but also withstand the impact of aggressive well fluids (moisture, sour gases, saline solutions) at high downhole temperatures. When proppant particles are destroyed under the impact of well fluids, the created fractures tend to close and this may result in reduction of well yield. On a commercial scale, proppants are obtained by processing of feedstock (silica sand, bauxite, kaolin, alumina oxides, various aluminosilicate type of feedstock).